How to Build a Ladder for a Bunk Bed

Building a ladder for a bunk bed is necessary if you have custom-built beds or if the original ladder needs replacing. The two primary types of bunk bed ladder are straight up and down and angled out. This how-to will show you how to build an angled ladder. 

Step 1: Determine Slope of Ladder

On its short edge, hold one length of 2x4 in place against the upper rail and, with the sliding bevel, determine the angle you'll build the ladder in relation to it. At the backside of the foot of the 2x4, mark where it will meet the floor. As an example, assume the angle measures 15°. 

Step 2: Measure and Cut Foot of Ladder Sides

At the mark you made on the 2x4 side, draw a straight line across the face. Set the bevel to 15° and draw a line at that angle to the right of the straight line from the same starting point. Cut along the angled line with the circular saw. Cut the second side at the same point at the same angle. 

Step 3: Cut the Tops of the Sides

Set the sides flush on the floor and up against the rail. Mark the 2x4s about 3 inches above the rail and cut the tops off of both sides with the saw. 

Step 4: Cut the Rungs

Decide on a length and cut equal pieces of 1x4 to affix between the sides of the ladder. How many rungs you place will depend upon the height of the ladder. Don't place them more than 12 inches apart on center, beginning no higher than 8 inches off the ground. 

Step 5: Space the Rungs

Starting 8 inches off the floor, make a mark on both side pieces of the ladder. Space the rungs 10 inches apart. Measure up equally on both pieces and make a second mark on each, continuing up both sides. The last rung should not be placed above the rail of the upper bunk. 

Step 6: Angle the Rungs

At the marks you made on the side, hold the T-square against the broad face of the side at 90° to its long edge. Draw a straight line across the face over this mark. Set the sliding bevel to 15° and, from the outside edge of the side, draw a line 15° off the straight line. Make sure this is done on the inside face of either side at each mark. 

Step 7: Drill Pilot Holes

The lines you've drawn for the rungs should be parallel to the floor when the sides are in place. With the power drill, make 2 pilot holes on each line from the inside out through the 2x4s. Drill a countersink into the outside of each of the pilot holes. 

Step 8: Preset Wood Screws

From the outside in, preset two 3½-inch wood screws into each hole. There should be 2 per rung, per side. Set them so the tips barely show on the inside. 

Step 9: Sand Rung Edges

With the power sander, round out the sharp top and bottom edges of each rung on the front and top edge on the back. Follow this with light sandpaper to smooth out any rough spots. 

Step 10: Attach Rungs

Apply wood glue to the edge you're attaching and abut it up to the side so the preset wood screws are centered on the edge of the rung. Holding it in place, set the screws into the countersunk holes. Complete one side at a time.

Step 11: Primer and Paint

Sand the ladder down before you apply the primer to ensure that it's smooth. Apply at least one coat of primer or a second if the instructions call for it. After the primer dries, coat it with the paint of your choice. Allow the ladder to dry completely.

Step 12: Attach Flat Metal Hooks

On the backside of the ladder sides where they meet the bunk rail, eyeball the position of the 2 metal hooks. Drill pilot holes for the hardware to attach the hooks into the 2x4s. Hold the hook in position and set the hardware screws until it's secure.

Once secure, your bunk bed ladder should safely lock onto the upper rail and provide a flat surface for little feet to climb.